release/src-rt-6.x.4708/linux/linux-2.6.36/arch/m32r/mm/init.c

   1 /*
   2  *  linux/arch/m32r/mm/init.c
   3  *
   4  *  Copyright (c) 2001, 2002  Hitoshi Yamamoto
   5  *
   6  *  Some code taken from sh version.
   7  *    Copyright (C) 1999  Niibe Yutaka
   8  *    Based on linux/arch/i386/mm/init.c:
   9  *      Copyright (C) 1995  Linus Torvalds
  10  */
  11
  12 #include <linux/init.h>
  13 #include <linux/kernel.h>
  14 #include <linux/mm.h>
  15 #include <linux/pagemap.h>
  16 #include <linux/bootmem.h>
  17 #include <linux/swap.h>
  18 #include <linux/highmem.h>
  19 #include <linux/bitops.h>
  20 #include <linux/nodemask.h>
  21 #include <linux/pfn.h>
  22 #include <linux/gfp.h>
  23 #include <asm/types.h>
  24 #include <asm/processor.h>
  25 #include <asm/page.h>
  26 #include <asm/pgtable.h>
  27 #include <asm/pgalloc.h>
  28 #include <asm/mmu_context.h>
  29 #include <asm/setup.h>
  30 #include <asm/tlb.h>
  31
  32 /* References to section boundaries */
  33 extern char _text, _etext, _edata;
  34 extern char __init_begin, __init_end;
  35
  36 pgd_t swapper_pg_dir[1024];
  37
  38 DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
  39
  40 /*
  41  * Cache of MMU context last used.
  42  */
  43 #ifndef CONFIG_SMP
  44 unsigned long mmu_context_cache_dat;
  45 #else
  46 unsigned long mmu_context_cache_dat[NR_CPUS];
  47 #endif
  48 static unsigned long hole_pages;
  49
  50 /*
  51  * function prototype
  52  */
  53 void __init paging_init(void);
  54 void __init mem_init(void);
  55 void free_initmem(void);
  56 #ifdef CONFIG_BLK_DEV_INITRD
  57 void free_initrd_mem(unsigned long, unsigned long);
  58 #endif
  59
  60 /* It'd be good if these lines were in the standard header file. */
  61 #define START_PFN(nid)          (NODE_DATA(nid)->bdata->node_min_pfn)
  62 #define MAX_LOW_PFN(nid)        (NODE_DATA(nid)->bdata->node_low_pfn)
  63
  64 #ifndef CONFIG_DISCONTIGMEM
  65 unsigned long __init zone_sizes_init(void)
  66 {
  67         unsigned long  zones_size[MAX_NR_ZONES] = {0, };
  68         unsigned long  max_dma;
  69         unsigned long  low;
  70         unsigned long  start_pfn;
  71
  72 #ifdef CONFIG_MMU
  73         start_pfn = START_PFN(0);
  74         max_dma = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
  75         low = MAX_LOW_PFN(0);
  76
  77         if (low < max_dma){
  78                 zones_size[ZONE_DMA] = low - start_pfn;
  79                 zones_size[ZONE_NORMAL] = 0;
  80         } else {
  81                 zones_size[ZONE_DMA] = low - start_pfn;
  82                 zones_size[ZONE_NORMAL] = low - max_dma;
  83         }
  84 #else
  85         zones_size[ZONE_DMA] = 0 >> PAGE_SHIFT;
  86         zones_size[ZONE_NORMAL] = __MEMORY_SIZE >> PAGE_SHIFT;
  87         start_pfn = __MEMORY_START >> PAGE_SHIFT;
  88 #endif /* CONFIG_MMU */
  89
  90         free_area_init_node(0, zones_size, start_pfn, 0);
  91
  92         return 0;
  93 }
  94 #else   /* CONFIG_DISCONTIGMEM */
  95 extern unsigned long zone_sizes_init(void);
  96 #endif  /* CONFIG_DISCONTIGMEM */
  97
  98 /*======================================================================*
  99  * paging_init() : sets up the page tables
 100  *======================================================================*/
 101 void __init paging_init(void)
 102 {
 103 #ifdef CONFIG_MMU
 104         int  i;
 105         pgd_t *pg_dir;
 106
 107         /* We don't need kernel mapping as hardware support that. */
 108         pg_dir = swapper_pg_dir;
 109
 110         for (i = 0 ; i < USER_PTRS_PER_PGD * 2 ; i++)
 111                 pgd_val(pg_dir[i]) = 0;
 112 #endif /* CONFIG_MMU */
 113         hole_pages = zone_sizes_init();
 114 }
 115
 116 int __init reservedpages_count(void)
 117 {
 118         int reservedpages, nid, i;
 119
 120         reservedpages = 0;
 121         for_each_online_node(nid) {
 122                 unsigned long flags;
 123                 pgdat_resize_lock(NODE_DATA(nid), &flags);
 124                 for (i = 0 ; i < MAX_LOW_PFN(nid) - START_PFN(nid) ; i++)
 125                         if (PageReserved(nid_page_nr(nid, i)))
 126                                 reservedpages++;
 127                 pgdat_resize_unlock(NODE_DATA(nid), &flags);
 128         }
 129
 130         return reservedpages;
 131 }
 132
 133 /*======================================================================*
 134  * mem_init() :
 135  * orig : arch/sh/mm/init.c
 136  *======================================================================*/
 137 void __init mem_init(void)
 138 {
 139         int codesize, reservedpages, datasize, initsize;
 140         int nid;
 141 #ifndef CONFIG_MMU
 142         extern unsigned long memory_end;
 143 #endif
 144
 145         num_physpages = 0;
 146         for_each_online_node(nid)
 147                 num_physpages += MAX_LOW_PFN(nid) - START_PFN(nid) + 1;
 148
 149         num_physpages -= hole_pages;
 150
 151 #ifndef CONFIG_DISCONTIGMEM
 152         max_mapnr = num_physpages;
 153 #endif  /* CONFIG_DISCONTIGMEM */
 154
 155 #ifdef CONFIG_MMU
 156         high_memory = (void *)__va(PFN_PHYS(MAX_LOW_PFN(0)));
 157 #else
 158         high_memory = (void *)(memory_end & PAGE_MASK);
 159 #endif /* CONFIG_MMU */
 160
 161         /* clear the zero-page */
 162         memset(empty_zero_page, 0, PAGE_SIZE);
 163
 164         /* this will put all low memory onto the freelists */
 165         for_each_online_node(nid)
 166                 totalram_pages += free_all_bootmem_node(NODE_DATA(nid));
 167
 168         reservedpages = reservedpages_count() - hole_pages;
 169         codesize = (unsigned long) &_etext - (unsigned long)&_text;
 170         datasize = (unsigned long) &_edata - (unsigned long)&_etext;
 171         initsize = (unsigned long) &__init_end - (unsigned long)&__init_begin;
 172
 173         printk(KERN_INFO "Memory: %luk/%luk available (%dk kernel code, "
 174                 "%dk reserved, %dk data, %dk init)\n",
 175                 nr_free_pages() << (PAGE_SHIFT-10),
 176                 num_physpages << (PAGE_SHIFT-10),
 177                 codesize >> 10,
 178                 reservedpages << (PAGE_SHIFT-10),
 179                 datasize >> 10,
 180                 initsize >> 10);
 181 }
 182
 183 /*======================================================================*
 184  * free_initmem() :
 185  * orig : arch/sh/mm/init.c
 186  *======================================================================*/
 187 void free_initmem(void)
 188 {
 189         unsigned long addr;
 190
 191         addr = (unsigned long)(&__init_begin);
 192         for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
 193                 ClearPageReserved(virt_to_page(addr));
 194                 init_page_count(virt_to_page(addr));
 195                 free_page(addr);
 196                 totalram_pages++;
 197         }
 198         printk (KERN_INFO "Freeing unused kernel memory: %dk freed\n", \
 199           (int)(&__init_end - &__init_begin) >> 10);
 200 }
 201
 202 #ifdef CONFIG_BLK_DEV_INITRD
 203 /*======================================================================*
 204  * free_initrd_mem() :
 205  * orig : arch/sh/mm/init.c
 206  *======================================================================*/
 207 void free_initrd_mem(unsigned long start, unsigned long end)
 208 {
 209         unsigned long p;
 210         for (p = start; p < end; p += PAGE_SIZE) {
 211                 ClearPageReserved(virt_to_page(p));
 212                 init_page_count(virt_to_page(p));
 213                 free_page(p);
 214                 totalram_pages++;
 215         }
 216         printk (KERN_INFO "Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
 217 }
 218 #endif